EP4157161B1 - Input device for operating and/or controlling a technical device via a user - Google Patents

Description

The present invention relates to an input device for operating and/or controlling a technical device by a user, with a plurality of sensor elements which are designed to be spatially distributed in the oral cavity of the user in order to detect a respective current tongue position and/or tongue movement of the user, and with an interface circuit which is coupled to the sensor elements and which is designed to generate a plurality of control signals depending on the sensor elements and to transmit them to the technical device.

The invention further relates to a method for operating and/or controlling a technical device by a user, comprising the steps of: providing a plurality of sensor elements spatially distributed in the oral cavity of the user, detecting a respective current tongue position and/or tongue movement of the user using the sensor elements, generating a plurality of control signals depending on the respective current tongue position and/or tongue movement of the user with the aid of an interface circuit, and transmitting the plurality of control signals from the interface circuit to the technical device.

Such an input device and a corresponding method are in principle US 2012/0259554 A1 which can also be regarded as the closest state of the art.

There are numerous different concepts to enable a user to interact with a technical device and in particular to generate data and/or control commands for the technical device. Keyboards, mice, so-called trackballs and touch-sensitive surfaces in the form of touchscreens or touchpads are known for entering data or commands for a computer. What these input devices have in common is that the user typically uses his hands or at least one or more fingers are required to operate the technical device. Accordingly, this can be referred to as a manual input device.

In addition, voice-controlled input devices are increasingly being used. However, there are situations and constellations in which a user cannot interact with a technical device either manually or voice-controlled, for example due to a physical disability or due to another manual activity being carried out at the same time in an environment in which voice input could be unreliable, disruptive or even treacherous.

The above mentioned US 2012/0259554 A1 proposes an input device for a computer in which the tongue movement of a user is tracked within the oral cavity. In a first embodiment, the input device includes a magnetic ball that can rotate freely within a ball cage. The ball cage with the ball can be placed in the user's oral cavity via a mouthpiece and the user can move the ball with his tongue. A magnetic sensor is provided outside the oral cavity that detects changes in the magnetic field of the ball. In a second embodiment, the input device includes a plurality of pressure sensors or a plurality of capacitive sensors that are arranged on a mouthpiece that can be pushed over the user's teeth. It is proposed here that the sensors are placed visibly on the outside or front of the teeth. The pressure sensors can detect sufficient pressure that a user can generate with his tongue. Capacitive sensors can detect the proximity of the tongue even without contact. The signals from the sensors are to be transmitted wirelessly to a processor, which can serve as an interface circuit to a computer. The required radio signals are to be generated by the sensor elements in response to a specific tongue movement of the user. This indicates that the sensors require a power supply that is not shown in detail. In a third embodiment, US 2012/0259554 A1 proposes that the tongue movement of the user is tracked using a thermal camera arranged in the oral cavity. Further embodiments include microphones outside the oral cavity with which the tongue movement is to be tracked. Overall, US 2012/0259554 A1 thus a variety of Concepts that are intended to enable a user to operate and/or control a technical device with the tongue.

Another input device for operating and/or controlling a technical device using the tongue is US 2016/0154468 A1 In a first embodiment, the device includes a rod with integrated sensor elements, which is attached to the user's tongue, for example by a piercing. The sensor elements in the rod can include a rotation rate sensor, a pressure sensor and/or a touch-sensitive sensor, so that the user can interact with a technical device by placing the tongue against the palate or by other tongue movements. In a further embodiment, a touch-sensitive sensor element can be arranged as a dental implant in the user's oral cavity.

Yet another input device for operating and/or controlling a technical device using the tongue is described in US7,995,031 B2 In this case, the input device includes pressure sensors that are placed under the palate. Another input device with pressure sensors is disclosed in US8,242,880 B2 disclosed. US8,018,320 B2 proposes a tongue-controlled input device based on induction. US8,548,394 B2 discloses a tongue-controlled input device which is placed under the palate and is based on induction, on a mechanical interaction or on a touch-sensitive surface.

Out of US 2018/0000563 A1 A radio module is known that is used to monitor tooth alignment as part of orthodontic treatment. Furthermore, the radio module can be used to monitor parameters relating to a person's breathing and sleep. The radio module can be attached to a patient's teeth using a carrier.

WO 2006/073296 A1 discloses an RFID tag for attachment to a human tooth. The RFID tag contains a memory for storing personal information that is intended to identify the wearer, particularly in the event of an accident.

US8,487,769 B2 reveals a switchable RFID transponder. US 2013/090921 A1 discloses an input device for voice input.

WO90/07249 A1 discloses a tongue-activated communications controller having an intraoral transmitter assembly with a keyboard having a plurality of tongue-activated positions for encoding a signal. The intraoral transmitter assembly includes a two-sided circuit board. The first side contains electronics for transmitting signals and the second side contains circuitry for switching from one position to another. The controller also includes a receiver for receiving the encoded signals from the transmitter. The receiver sends the signal to a microcomputer for decoding the encoded signals to form from the decoded signal a set of instructions for operating a device. The microcomputer sends the signals to a device to be operated.

EP 0 487 027 A1 discloses an operating device for physically handicapped persons with a switching device consisting of a circuit board with a keypad. The circuit board can be positioned in the mouth, for example, like a chewing gum board, so that the keypad can be operated with the tongue. Signals triggered in this way are transmitted to an interface via which various devices can be operated or controlled.

Against this background, it is an object of the present invention to provide an alternative input device that enables reliable operation and/or control of a technical device using the tongue. In particular, it is an object of the invention to provide an input device that enables a wide variety of user inputs and reduces incorrect inputs as much as possible. An input device is desirable that enables comfortable and safe/non-dangerous interaction with a technical device using the tongue for the user.

The tasks are solved by an input device of the type mentioned above, whereby the sensor elements each contain a transponder which is set up to is to receive an interrogation signal and, depending on this, to transmit an individually coded response signal with an individual coding to the interface circuit, wherein the interface circuit is set up to generate the interrogation signal and transmit it into the user's oral cavity via an antenna, and wherein the interface circuit can recognize, based on the individual coding, which of the sensor elements in the user's oral cavity a respective response signal originates from. Furthermore, a method of the type mentioned at the outset is proposed, wherein the interface circuit generates an interrogation signal and transmits it into the user's oral cavity via an antenna, and wherein the sensor elements each contain a transponder which receives the interrogation signal and transmits an individually coded response signal with an individual coding depending on the user's current tongue position and/or tongue movement to the interface circuit, wherein the interface circuit can recognize, based on the individual coding, which of the sensor elements in the user's oral cavity a respective response signal originates from.

In preferred embodiments, the sensor elements each contain a passive transponder, i.e. a transponder that generates the transmission energy required to generate the individually coded response signal from the query signal or receives it with the query signal. Accordingly, the sensor elements in the preferred embodiments do not require their own energy storage. In particular, a battery or a rechargeable accumulator in the oral cavity can be dispensed with, which is a great advantage in avoiding health impairments.

Irrespective of this, in other embodiments the input device could have an energy storage device in the form of a battery, a rechargeable battery or a capacitor, for example in the form of a so-called supercapacitor, whereby the energy storage device can be arranged together with the sensor elements in the user's oral cavity. Such an energy storage device can advantageously be charged without contact, in particular inductively or capacitively. In principle, such an energy storage device can also be charged with the help of so-called "energy harvesting" through the movement of the tongue itself.

In any case, the sensor elements of the new input device each have a transponder that is able to transmit an individually coded response signal to the interface circuit. Each sensor element therefore has "its own" transponder that identifies the sensor element. As a result, the interface circuit can easily and reliably identify which of the many sensor elements a particular response signal comes from. This makes it possible to identify the current position and/or movement of the tongue with a high spatial resolution and a high degree of reliability.

In particular, the new input device makes it possible to provide a large number of teeth with one or even several sensor elements in a very simple and cost-effective manner, in order to create a large number of "keys" for convenient and precise tongue-controlled input of data and/or control commands. The human tongue can locate the teeth in the user's oral cavity with a high degree of specificity and spatial resolution. In addition, the human tongue can detect even the smallest elevations, depressions and changes in the oral cavity. The new input device makes advantageous use of this property. In principle, one or even several sensor elements could be arranged on each of the user's teeth, for example on different sides of a tooth, including the inside of the tooth facing the tongue, the outside of the tooth facing away from the tongue and, if necessary, the chewing surfaces. The new input device thus opens up a large number of data and/or command inputs, which can be very reliably distinguished from one another due to the individual coding of the transponders, without the need for a complex evaluation circuit in the user's oral cavity. In principle, the new input device makes it possible to implement the assignment of a conventional computer keyboard with a corresponding ASCII character set.

A movement of the tongue along the inside of the teeth allows a user to interact very comfortably and without fatigue. Overall, the new input device enables a user to interact comfortably, reliably and safely with a technical device. The tasks mentioned above are therefore completely solved.

In a preferred embodiment, the sensor elements are each arranged on a sensor carrier which is designed to place the sensor elements on the user's teeth, in particular on the inner sides of the teeth which face the tongue.

Deviating from this or in addition to this, the sensor elements in other embodiments could be placed at other locations within the oral cavity of a user, for example on the palate or on the jawbone. The placement of the sensor elements on the teeth advantageously contributes to enabling error-free and comfortable interaction with the technical device because the teeth represent a reference position known and familiar to the user. It is particularly advantageous to place the individual sensor elements on the inside of the teeth because the user can then reach the sensor elements with very small fine motor movements. In some embodiments, the sensor carrier can hold a single sensor element on a tooth. In other embodiments, the sensor carrier can hold several sensor elements, for example in the manner of a bridge and/or as a mold model that is adapted as a negative impression to the outer contour of one or more teeth. In some embodiments, the sensor carrier can contain a silicone body that can be pushed over the user's teeth in the manner of a mouth guard or a dental splint. In other embodiments, the sensor elements can be glued to tooth surfaces, so that in these cases a housing wall of the respective sensor element, which can be fixed to one or more of the user's teeth using a body-compatible adhesive, forms or contains the sensor carrier. The positioning of these sensor elements can advantageously be carried out using an applicator. Multiple sensor elements may be arranged in groups on a common holder. In some embodiments, the input device may include sensor carriers that can each hold two sensor elements per tooth.

In a further embodiment, the input device includes a holder configured to hold the interface circuit outside the user's oral cavity.

Preferably, the holder is designed to hold the interface circuit in the head and/or neck area of the user. In some embodiments, the holder can have a bracket which, when used as intended, is arranged in the cheek area of the user and can be attached to the head and/or ear of the user, for example in the manner of a microphone headset. In further embodiments, the holder can be arranged in front of the user's face in the manner of a pair of glasses or can be placed around the user's neck on a collar or necklace. In further embodiments, the interface circuit can be mounted on a flexible film that adheres to the skin or as a so-called electronic tattoo that is positioned in the cheek, chin and/or neck area of the user. All of these designs and embodiments have the advantage that the transmission of the individual coding and the mutual exchange of query signal and response signal are made possible over short distances. This allows the new input device to be implemented with very low transmission power, which appears to be advantageous both for the operating time and for the health of the user.

In a further embodiment, the sensor elements each contain a SAW tag as a transponder.

The abbreviation SAW stands for surface acoustic wave and refers to a sound wave that spreads across the surface of a body. In this embodiment, the sensor elements contain a wave converter (typically as an interdigital converter) that converts an electrical, magnetic and/or electromagnetic query signal into a mechanical sound wave. The sound wave can spread across the surface of the carrier body and is reflected at defined reflection points. A sound wave reflected in this way runs back along the surface of the body and is emitted by the wave converter as a response signal. In preferred embodiments, each sensor element has a SAW tag with an individual coding in the form of a spatial distribution of reflection points, so that the individually encoded response signal contains a large number of reflections, the time interval of which relative to the query signal and relative to one another represents the individual coding.

The use of such SAW tags enables a very cost-effective and reliable identification of the individual sensor elements. The sound wave on the surface of the sensor element spreads more slowly than an electromagnetic radio wave, which in principle leads to a time delay between the query signal and the individually coded response signals of the sensor elements. This time delay is very advantageous in order to evaluate a large number of individually coded response signals in response to a common query signal, especially in the Presence of natural reflections of the interrogation signal in the user's oral cavity. The delay also reduces direct crosstalk from the interrogation signal to the response signal on the interface circuit. Furthermore, unlike many other sensor elements, SAW tags can be manufactured with very small dimensions, for example less than or equal to 2mm x 2mm x 0.2mm. This facilitates positioning directly on the user's teeth. In some embodiments, the SAW tags can be provided with a body-compatible coating and attached to the user's teeth using a body-compatible adhesive. Such sensor elements can then advantageously be removed by simply brushing the teeth and excreted, for example, via the intestinal tract. This reduces or avoids hygiene problems.

In a further embodiment, the interface circuit is configured to analyze a plurality of individually coded response signals with respect to a respective signal strength.

In this embodiment, the evaluation of the sensor elements includes an analysis of the respective signal strength in addition to the interface circuit analyzing the respective individual coding of the sensor elements. The analysis of the respective signal strength can be carried out in some embodiments using a threshold criterion in that the interface circuit first decides on the basis of a threshold criterion which response signals from the multitude of response signals of the sensor elements are to be sent for further analysis/evaluation. In some preferred embodiments, the interface circuit is set up to analyze only those individually coded response signals in relation to the respective individual code whose signal strength exceeds or at least reaches a defined threshold value. The embodiment enables the new input device to be implemented in a very simple and cost-effective manner with purely passive sensor elements, since the tongue dampens or even suppresses a signal exchange between a sensor element and the interface circuit when it covers the sensor element. Accordingly, the input device of this embodiment can be based on the user using his tongue to specifically dampen a signal exchange between the interface circuit and one or more selected sensor elements. and/or suppress it. Advantageously, the interface circuit can store which individually coded response signals the interface circuit can expect in response to a query signal if none of the sensor elements or only certain sensor elements are covered by the user's tongue. The interface circuit can be set up to compare the received response signals with the expected setting in order to recognize in this way which sensor element or sensor elements did not receive a response signal with sufficient signal strength. In this way, the interface circuit can very easily recognize the "activation" of a sensor element with the tongue, more precisely a desired association between the tongue and tooth or teeth.

In a further embodiment, the interface circuit is designed to logically link a plurality of individually coded response signals.

This design advantageously contributes to the interface circuit being able to reliably detect and evaluate simultaneous and/or chronologically successive "activations" of a group of sensor elements. In some embodiments of this design, the interface circuit is particularly advantageously set up to detect a tongue movement along several sensor elements in relation to the direction of movement and/or speed of movement. This enables the user to interact with the technical device, for example, via "swiping movements" similar to a touch-sensitive screen of a smartphone or tablet PC. For example, a movement with the tongue from left to right along the inside of the teeth in the user's upper jaw could function as an input command for a technical device that triggers a movement of the device to the right. The technical device can be an assistive robot system, for example. The detection and ignoring of possibly unintentional multiple activations and a resulting increase in the reliability of the new input device is also made easier with this design.

In a further embodiment, the sensor elements each contain a switch which is designed to selectively activate or deactivate the transponder.

In some embodiments of this design, the switch can be configured to selectively establish or interrupt an electrical connection between a first part of the sensor element and a second part of the sensor element, wherein the first part of the sensor element includes an antenna via which the query signal is received and/or the response signal is sent, while the second part stores or represents the individual coding of the respective sensor element. In some embodiments, the switch can be an electrical contact that can optionally be closed with the tongue. In particular, the switch can include a changeover contact with which a first sensor element or a second sensor element can optionally be activated.

This design is particularly advantageous if the interface circuit is only to receive an individually coded response signal from those sensor elements that are selected by a user action. The design enables rapid detection of a sensor element activated by the user with the tongue. It also helps to give the user haptic feedback for the actuation of a sensor element. This can be advantageous for reducing incorrect inputs.

In a further embodiment, the sensor elements each have a defined contact surface for the user's tongue, wherein the switch can be actuated perpendicular to the contact surface.

In this design, the sensor elements can act like a push button, which enables very reliable individual actuation of individual sensor elements with the tongue.

In a further embodiment, the sensor elements each have a defined contact surface for the user's tongue, wherein the switch can be actuated parallel to the contact surface.

In this embodiment, the activation of a sensor element requires a sliding operation of the switch with the tongue or a Shear force, which advantageously contributes to reducing incorrect inputs. In addition, this design is advantageous if a sensor element is to optionally generate two different response signals in order to further increase the number of possible interactions of the user with the technical device.

In a further embodiment, the sensor elements each have a raised area and/or a recess that provides the user's tongue with a tactile marking.

This design advantageously contributes to improving the ergonomics of the new input device and minimizing unintentional input errors.

In a further embodiment, the input device includes a jaw position sensor configured to detect a jaw position of the user, wherein the interface circuit is configured to generate the plurality of control signals further in dependence on the jaw position sensor.

This design advantageously contributes to further increasing the number of possible user inputs. In some preferred embodiments, the jaw position sensor can function like a shift key, so that the user can bring about various interactions with the technical device by opening or closing his jaw in addition to a tongue movement. In preferred embodiments, the interface circuit is accordingly set up to generate various control signals for an individually coded response signal of a selected sensor element depending on a signal from the jaw position sensor. In some embodiments, the jaw position sensor can be set up to detect an opening angle between the upper jaw and the lower jaw of the user. In further embodiments, the jaw position sensor can be set up to generate a pressure-dependent jaw position signal, which can be representative, for example, of the pressure with which the upper jaw and the lower jaw are pressed against each other.

In a further embodiment, the sensor elements each have a closed biocompatible shell.

A biocompatible casing in the sense of this embodiment is a closed casing made of a material that is free from harmful influences when in contact with the user's saliva and/or tissue. In some embodiments, the sensor elements can be coated with proteins in order to achieve biocompatibility. The sensor elements of this embodiment have a high body compatibility and are preferably biotolerant or even bioinert.

It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

Fig. 1

eine schematische Darstellung eines ersten Ausführungsbeispiels der neuen Vorrichtung,

Fig. 2

eine schematische Darstellung eines SAW-Tags, der in dem Ausführungsbeispiel gemäß Fig. 1 als Sensorelement verwendet sein kann,

Fig. 3

eine schematische Darstellung eines weiteren Ausführungsbeispiels mit mehreren Sensorelementen,

Fig. 4

eine schematische Darstellung eines Sensorelements gemäß einem weiteren Ausführungsbeispiel, und

Fig. 5

eine schematische Darstellung eines Sensorelements gemäß einem noch weiteren Ausführungsbeispiel.

Embodiments of the invention are shown in the drawing and are explained in more detail in the following description. They show:

Fig.1

a schematic representation of a first embodiment of the new device,

Fig.2

a schematic representation of a SAW tag used in the embodiment according to Fig.1 can be used as a sensor element,

Fig.3

a schematic representation of another embodiment with several sensor elements,

Fig.4

a schematic representation of a sensor element according to another embodiment, and

Fig.5

a schematic representation of a sensor element according to yet another embodiment.

In Fig.1 an embodiment of the new input device is designated in its entirety with the reference number 10. The input device 10 serves to enable a human user to interact with a technical device, as is explained in detail below. The user is shown here in a highly simplified manner with his oral cavity 12, in which the tongue 14 and a plurality of teeth 16 are located. In the embodiment shown, a sensor element 18 is arranged on each of the teeth 16 on an inner side of the tooth facing the tongue 14. In some embodiments, the sensor elements 18 each have a closed outer shell and are glued to a tooth with this outer shell. In other embodiments, the sensor elements can be attached to a sensor carrier (not shown here), wherein the sensor carrier is attached to the user's teeth. In some embodiments, the sensor carrier can be attached to the user's teeth in a similar way to braces. Alternatively, the sensor carrier can contain a plastic rail with a negative mold of the teeth that can be pushed over the teeth. Regardless of the type of attachment of the sensor elements to the user's teeth, it is preferred in some embodiments if at least six discrete sensor elements are distributed within the oral cavity, with each discrete sensor element being arranged on a different tooth.

The input device 10 includes an interface circuit 20, which in preferred embodiments may include a microcontroller, microprocessor, ASIC, FPGA or other logic circuit. In the preferred embodiments, the interface circuit is held outside the user's oral cavity. For example, the interface circuit 20 can be held by means of a bracket 22, which is attached to one or both ears of the user in the manner of a headset. In further embodiments, the interface circuit 20 can be arranged on a chain or a collar that the user can wear around the neck. In further embodiments, the interface circuit 20 can be arranged on glasses or a glasses-like frame, a helmet or a similar holder that allows a user to position the interface circuit 20 in the head area. In preferred embodiments, the interface circuit 20 has an antenna 24, which, for example, extends in a bracket-like manner along the jawbone and/or one side of the cheek of the user or can be applied directly to the user's skin as an electronic tattoo.

In the exemplary embodiment shown here, the interface circuit 20 is connected to an electric drive 26 and a computer 28. The electric drive 26 and the computer 28 are examples of a technical device that the user can operate and/or control using the new input device 10. For example, the drive 26 and the computer 28 can be parts of an assistive robot system. In general, the input device 10 can be used anywhere where manual or voice-based data and/or command input for a technical device is not possible, only temporarily or only inadequately possible, in particular in the field of healthcare, in military applications such as adjusting a rifle scope in the firing position, or in the leisure and sports sector, such as in so-called action sports. In some exemplary embodiments, the interface circuit 20 can optionally be coupled to several technical devices that are spatially positioned apart from one another, for example in different rooms of a building. The user can then operate and/or control the various technical devices with one and the same input device 10, depending on which of the various technical devices he is in the vicinity of at a defined point in time. Accordingly, in preferred embodiments, the interface circuit 20 can have a radio interface to the technical device, which is designed, for example, as a WLAN and/or Bluetooth and/or NFC interface.

As in Fig.1 As is indicated schematically, the interface circuit 20 generates a query signal 30, which is transmitted here via the antenna 24 into the oral cavity 12 of the user. The sensor elements 18 each have a - preferably passive - transponder, which is able to receive the query signal 30 and, depending on this, to generate an individually coded response signal 32, 34. By way of example, a first individual code is shown at the reference number 32' and a different second individual code is shown at the reference number 34'. The response signal 32 with the individual code 32' is generated by a sensor element 18', which is arranged on the tooth 16'. The response signal 34 with the individual code 34' is generated by a sensor element, which is arranged on the tooth 16". Due to the different individual codings 32', 34', the interface circuit 20 can recognize from which of the sensor elements 18 in the oral cavity 12 of the user a respective response signal 32, 34 originates.

In the Fig.1 In the situation shown, the tip of the tongue 14 touches the inside of the tooth 16', on which the sensor element 18' is arranged. Accordingly, the tongue 14 covers the sensor element 18' here, which means that the response signal 32 is dampened in comparison to the response signal 34 or is even completely suppressed. As a result, the interface circuit 20 receives the response signal 34 of the sensor element 18" on the tooth 16" via the antenna 24 significantly more strongly than the response signal 32 from the tooth 16'. The same applies here to further response signals (not shown here) from the other sensor elements 18 in the oral cavity 12 of the user. By analyzing the response signals from all sensor elements 18 in the oral cavity 12 and comparing them with an expectation that can be stored, for example, in an internal memory of the interface circuit 12, the interface circuit 20 can recognize that the tip of the tongue is resting on the tooth 16'. In the preferred embodiments, the interface circuit 20 interprets this as an "actuation" of the sensor element 18' on the tooth 16' and determines a control signal for the technical device in response to this actuation. In some embodiments, the control signal may correspond to the actuation of a key on a commercially available computer keyboard, so that the user can generate keystrokes with his tongue that are compatible with the keystrokes of a commercially available computer keyboard. In other embodiments, the actuation of the sensor element 18' may, for example, turn the electric drive 26 on or off.

In preferred embodiments, the input device 10 includes one or more jaw position sensors 36, with which the position of the user's lower jaw relative to the upper jaw and/or a pressure with which the user presses the lower jaw and the upper jaw together can be detected. The jaw position sensor can also be arranged outside the oral cavity 12, in particular on the user's skin in the area of the discus articularis. The jaw position sensor can be attached to the bracket 22, for example. In preferred embodiments, the jaw position sensor 36 generates a further individually coded response signal 38 in response to the Query signal 30. The interface circuit 20 can detect a current jaw position of the user with the help of the jaw position sensor 36 and generate various control signals for the technical device depending on this. In some embodiments, the interface circuit 20 can logically combine the jaw position signal 38 in the manner of a shift key or selection key with the actuation of a sensor element 18 by the tongue 14, so that the user can generate various "characters" with the same tongue position or tongue movement by varying his jaw position.

In preferred embodiments, the interface circuit 20 is configured to determine a temporal sequence of tongue positions in order to detect a tongue movement within the oral cavity 12. In some preferred embodiments, the user can use a controlled tongue movement to effect an interaction with the technical device, such as a movement of the technical device in a direction of movement that corresponds to the direction of movement of the tongue 14.

In preferred embodiments, the interface circuit 20 analyzes multiple actuations of sensor elements 18 within a defined period of time in order to detect, in particular, simultaneous or almost simultaneous actuations of sensor elements 18. In some preferred embodiments, multiple actuation of sensor elements 18 with the tongue 14 can cause a targeted interaction with the technical device, similar to how the simultaneous actuation of several keys on the keyboard of a conventional computer can trigger predefined actions. In other embodiments, the interface circuit 20 can be set up to ignore multiple actuations of sensor elements 18 within the defined period of time or to compare them with a stored expectation for typical uncontrolled tongue movements in order to filter out unwanted or uncontrolled tongue movements.

Fig.2 shows a preferred embodiment of a sensor element 18, but here in a schematic representation without a biocompatible sheath.

The sensor element 18 here has a body 40, which can be made, for example, from a crystalline semiconductor material such as lithium niobate LiNbO3. In this case, the body can be very thin and have a thickness of, for example, less than or equal to 0.2 mm. Conductor structures are formed on the body 40, for example as metallic tracks. A first conductor structure 42 forms a wave converter (interdigital converter) with a receiving antenna 44, via which the electrical, magnetic and/or electromagnetic interrogation signal 30 can be received. An electrical interrogation signal can be used as part of a capacitive coupling between the sensor elements and the interface circuit. A magnetic interrogation signal can be used for an inductive coupling between the sensor elements and the interface circuit. An electromagnetic interrogation signal 30 corresponds to a radio signal. In principle, all three variants appear possible, with an electromagnetic interrogation signal 30 appearing advantageous with regard to the function of the sensor element 18 explained below.

The conductor structure 42 converts the interrogation signal 30 into an acoustic surface wave, which Fig.2 is indicated by the reference number 46. The surface wave 46 spreads on the surface of the body 40 in the direction of the arrow 48. The reference number 50 shows a further conductor structure which is formed on the surface of the body 40. The further conductor structure 50 essentially contains several reflectors at which the surface wave 46 is reflected. A reflected surface wave 52 is therefore created at each reflector of the conductor structure 50, which runs in the direction of the arrow 54 and reaches the conductor structure 42. There, the returning surface wave 52 is converted back into an electromagnetic wave and emitted via the antenna 44.

The conductor structure 42 and the antenna 44 are preferably matched to one another, with high impedance and preferably directly coupled to enable advantageous miniaturization of the sensor element 18. In some embodiments, the sensor element 18 has a surface area of approximately 2mm x 2mm.

In the lower part of the Fig.2 A schematic timing diagram is shown, which shows a pulse at reference number 56, which symbolizes the interrogation signal 30. The pulse 56 excites an incoming surface wave 46 in the first conductor structure 42. The reference numbers 58, 60, 62 show three smaller pulses which follow one another in time and occur with a certain time delay Δt ₀ after the pulse 56. The pulses 58, 60 are shown here with a time interval Δt which corresponds to the spatial distance d between the first two reflectors of the second conductor structure 50 in the direction of travel 48 of the incoming surface wave 46. In other words, the sensor element 18 generates a number of temporally staggered response pulses 58, 60, 62 in response to a query pulse 56, the time interval of the response pulses 58, 60, 62 to the query pulse 56 and relative to one another corresponding to the spatial arrangement and distance of the reflectors in the conductor structure 50 relative to the conductor structure 42. The signal strength of the response pulses 58, 60, 62, which are emitted by the first conductor structure 42 as an electromagnetic wave and then arrive at the antenna 24 of the interface circuit 20, is usually significantly lower than the signal strength of the interrogation pulse 56, as shown in Fig.2 is shown in a simplified manner, since the energy of the query pulse 56 is distributed over several response pulses 58, 60, 62. The time interval Δt ₀ of the response pulses 58, 60, 62 to the query signal 56 is, due to the propagation speed of the acoustic surface waves 46, 52, significantly greater than the time offset to backscatter signals or signal echoes of the query signal 56 due to reflections in the oral cavity. The time interval Δt ₀ simplifies the evaluation of the response pulses 60, 62 in the interface circuit 20.

Reference number 64 indicates a threshold line that represents a signal threshold that is stored in the interface circuit 20. Only when a sequence of response pulses 58, 60, 62 exceeds the signal threshold represented by line 64 does the interface circuit 20 in this embodiment recognize the corresponding pulse sequence as a response signal from the sensor element 18. The time interval Δt between the individual response pulses in the pulse sequence 58, 60, 62 represents an individual coding that uniquely identifies the corresponding sensor element 18. Fig.2 shows a simplified representation of a so-called SAW tag and an illustration of an advantageous mode of operation. SAW tags have been around since the 1960s and they form a kind of geometrically coded transponder that is particularly well suited for the implementation of the new input device because SAW tags are passive Transponders can be manufactured very small and inexpensively. As already indicated above, the user can use his tongue to attenuate the signal strength of the electromagnetic wave that reaches a SAW tag as an interrogation signal 30, as well as the signal strength of any response pulses 58, 60, 62, and thus help the interface circuit 20 to receive the response signal 32 from the sensor element 18' (see Fig.1 ) or at least not with sufficient signal strength.

Fig.3 shows a further embodiment using two sensor elements 18a, 18b, which can be arranged on a tooth 16a, 16b of a user. The sensor elements 18a, 18b can be identified by means of SAW tags Fig.2 and/or using another transponder technology.

In the embodiment according to Fig.3 Two adjacent sensor elements 18a, 18b are held on a common sensor carrier 70. As already indicated above, the sensor carrier 70 can be made of silicone, plastic or metal and, depending on the application, can fix one or more sensor elements 18 to the teeth of a user. Suitable sensor carriers 70 are known in principle from the field of dentistry and jaw surgery.

A special feature of the embodiment according to Fig.3 is that here each of the sensor elements 18a, 18b contains two transmitting/receiving antennas 72, 74 which are arranged next to each other. Each of the two sensor antennas 72, 74 is "open" here, i.e. the electrical conductor track of the respective antenna 72, 74 is interrupted. A switch 76 with two contact paths is arranged between the two antennas 72, 74. The switch 76 can be moved with the tongue in the direction of the double arrow 78 in order to close either one antenna 72 or the other antenna 74. Each of the two antennas 72, 74 of a sensor element 18a, 18b can be coupled to a memory chip in which an individual coding is stored. The user can therefore selectively activate the sensor elements 18a, 18b with the help of his tongue and thereby select which of the respective codes is to be sent to the interface circuit 20 in response to a query signal 30. With such an embodiment, it is possible for a sensor element 18a, 18b to selectively send out different individual codes and thus send different operations to the interface circuit 20. In addition, an embodiment according to Fig.3 the direction of movement of the tongue and, if applicable, an oscillating movement of the tongue can be easily detected.

Fig.4 shows a simplified representation of a sensor element 18 with a contact surface 90, which is formed here on a raised portion 92. The contact surface 90 can be pressed onto a conductor track structure 94 by pressure perpendicular to the contact surface 90 in order to close an electrical contact. Fig.5 shows another embodiment of a sensor element with a switch, which here has to be moved parallel to the contact surface 90 in order to selectively open or close a double conductor structure 94. The Fig. 4 and 5 thus show possible realizations for a switch 76 according to Fig.3 .

In all preferred embodiments, the natural movement of the user's tongue 14 over the tooth surfaces facing into the interior of the oral cavity 12 enables largely fatigue-free operation of the input device 10. The arrangement of a single sensor element 18 on a tooth surface enables targeted data and/or control signal generation with a low error rate due to the fine motor skills or the fine motor memory of the tongue 14 within the oral cavity 12. An arrangement of the sensor elements on the inner surfaces of the teeth advantageously contributes to fatigue-free operation. A combined evaluation of the response signals from several sensor elements, possibly in combination with one or more signals that represent a jaw position of the user, is particularly advantageous, since in this way a very large number of different input data/commands can be distinguished from one another. Thus, embodiments of the new input device enable the implementation of a keyboard function as is known from conventional computer keyboards, but in contrast to manual operation, here with tongue operation.

Claims (15)

1. An input apparatus for operating and/or controlling a technical device (26, 28) by a user, comprising a plurality of sensor elements (18) which are configured to be arranged spatially distributed in the oral cavity (12) of the user in order to detect a respective current tongue position and/or tongue movement of the user, and comprising an interface circuit (20) which is coupled to the sensor elements (18) and which is configured to generate a plurality of control signals depending on the sensor elements (18) and to transmit them to the technical device (26, 28), characterized in that the sensor elements (18) each include a transponder which is configured to receive an interrogation signal (30) and to transmit an individually encoded response signal (32, 34) to the interface circuit (20) in response thereto, wherein the interface circuit (20) is configured to generate the interrogation signal (30).
2. The input apparatus according to claim 1, characterized in that the sensor elements (18) each are arranged on a sensor carrier (70) which is configured to place the sensor elements (18) on the user's teeth (16).
3. The input apparatus according to claim 1 or 2, characterized by a holder (22) configured to hold the interface circuit (20) outside the oral cavity (12).
4. The input apparatus according to any one of claims 1 to 3, characterized in that the sensor elements (18) each contain a SAW tag as a transponder.
5. The input apparatus according to any one of claims 1 to 4, characterized in that the interface circuit (20) is configured to analyze a plurality of individually encoded response signals (32, 34) with respect to their respective signal strength.
6. The input apparatus according to claim 4, characterized in that the interface circuit (20) is configured to compare the signal strength of a plurality of response signals (32, 34) with an expected value.
7. The input apparatus according to any one of claims 1 to 6, characterized in that the interface circuit (20) is configured not to evaluate a plurality of response signals (32, 34) below a defined threshold (64) with respect to signal strength.
8. The input apparatus according to any one of claims 1 to 7, characterized in that the interface circuit (20) is configured to logically interlink a plurality of individually encoded response signals (32, 34).
9. The input apparatus according to any one of claims 1 to 8, characterized in that the sensor elements (18) each include a switch (76) which is configured to selectively activate or deactivate the transponder.
10. The input apparatus according to claim 9, characterized in that the sensor elements (90) each have a defined contact surface for the tongue (14) of the user, wherein the switch can be actuated perpendicular to the contact surface (90).
11. The input apparatus according to claim 9 or 10, characterized in that the sensor elements each have a defined contact surface (90) for the tongue (14) of the user, wherein the switch can be actuated parallel to the contact surface (90).
12. The input apparatus according to any one of claims 1 to 11, characterized in that the sensor elements (18) each have a protrusion (92) and/or indentation that provides a tactile marker for the user's tongue (14).
13. The input apparatus according to any one of claims 1 to 12, characterized by a jaw position sensor (36) configured to detect a jaw position of the user, wherein the interface circuit (20) is configured to generate the plurality of control signals further depending on the jaw position sensor (36).
14. The input apparatus according to any one of claims 1 to 13, characterized in that the sensor elements (18) have a closed biocompatible shell.
15. A method for operating and/or controlling a technical device (26, 28) by a user, comprising the steps:

    - providing a plurality of sensor elements (18) spatially distributed in the oral cavity (12) of the user,

    - detecting a respective current tongue position and/or tongue movement of the user using the sensor elements (18),

    - generating a plurality of control signals depending on the respective current tongue position and/or tongue movement of the user by means of an interface circuit (20), and

    - transmitting the plurality of control signals from the interface circuit to the technical device (26, 28),

    characterized in that the interface circuit (20) generates an interrogation signal (30), and the sensor elements (18) each include a transponder that receives the interrogation signal (30) and transmits an individually encoded response signal (32, 34) to the interface circuit (20) depending on the respective current tongue position and/or tongue movement of the user.

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